面向循环经济的有机废弃物碳链延长制备中链脂肪酸：人工调控机制与工程化路径

吴雪姣; 马浩祎; 杨莹; 郑然; 董建; 崔寒; 张亚非; 周丹丹

doi:10.13205/j.hjgc.202608008

面向循环经济的有机废弃物碳链延长制备中链脂肪酸：人工调控机制与工程化路径

doi: 10.13205/j.hjgc.202608008

1. 东北师范大学环境学院, 长春 130117

基金项目:

国家自然科学基金青年基金项目“电子分叉介导的电驱动CO2一步生物甲烷化能量再生机制与调控研究”（22408130）；中央高校基本科研业务费专项资金（2412025QD030）

详细信息

作者简介:
吴雪姣（2001—），女，硕士研究生，主要研究方向为剩余污泥资源化利用。1061733228@qq.com

通讯作者:
张亚非（1990—），男，副研究员，主要研究方向为有机固废资源化利用。zhangyf228@nenu.edu.cn

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出版历程
- 收稿日期: 2026-05-31

Circular-economy-oriented medium-chain fatty acid production from organic wastes via chain elongation： artificial regulation and resource-loop pathways

1. School of Environment, Northeast Normal University, Changchun 130117, China

摘要

摘要: 中链脂肪酸（medium-chain fatty acids，MCFAs）具有较高能量密度、疏水性和化学转化价值，是连接有机废弃物资源化与循环经济发展的重要生物基产品。与传统厌氧消化产甲烷路径相比，碳链延长（chain elongation，CE）可通过逆β氧化（reverse β-oxidation，RBO）途径，将乙酸、乳酸、乙醇等短链中间产物进一步转化为己酸、辛酸等高附加值羧酸，为污泥、餐厨垃圾、农业废弃物、畜禽粪污和高浓度有机废水的资源化利用提供了新的技术方向。天然混合菌群驱动的CE体系受底物组成波动、电子供体竞争、产甲烷分流、目标产物选择性不足、产物毒性和分离成本较高等因素制约，尚难满足MCFAs稳定、高效和定向生产的需求。面向环境与循环经济交叉需求，围绕有机废弃物中碳资源和电子资源的定向回收，系统总结了CE制备MCFAs的代谢机制、人工调控策略及工程化瓶颈，并从连续流稳定运行、产物分离回收、技术经济性和生命周期评价等方面提出未来发展方向，以期为有机废弃物高值化利用和能碳资源协同优化提供参考。
- 碳链延长 /
- 中链脂肪酸 /
- 有机废弃物 /
- 循环经济 /
- 人工调控
Abstract: Medium-chain fatty acids （MCFAs） are promising biobased products due to their high energy density， hydrophobicity， and significant value for chemical conversion. They represent an important link between organic waste valorization and the development of a circular economy. Compared with conventional anaerobic digestion for methane production， chain elongation （CE） can further convert short-chain intermediates， such as acetate， lactate， and ethanol， into higher-value carboxylic acids， including caproate and caprylate， through the reverse β-oxidation （RBO） pathway. This process provides a novel approach for resource recovery from sewage sludge， food waste， agricultural residues， livestock manure， and high-strength organic wastewater. However， CE systems driven by natural mixed microbial communities are still constrained by fluctuations in substrate composition， competition for electron donors， carbon diversion to methanogenesis， insufficient product selectivity， product toxicity， and high separation costs， all of which limit the stable， efficient， and targeted production of MCFAs. Focusing on the interdisciplinary demands of environmental sustainability and circular economy development， this review systematically summarizes the metabolic mechanisms， artificial regulation strategies， and engineering challenges in MCFA production via CE， with particular emphasis on the directed recovery of carbon and electron resources from organic wastes. Future perspectives are proposed regarding stable continuous-flow operation， product separation and recovery， techno-economic assessment， and life cycle evaluation. This review aims to provide insights into the high-value utilization of organic wastes and the synergistic optimization of carbon and energy resource recovery.
- chain elongation /
- medium-chain fatty acids /
- organic waste /
- circular economy /
- artificial regulation

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